Merge pull request #1 from Flutter-Dart-Open-Source/nnbd

nnbd

Author: hoc081098

.github/workflows/flutter.yml

@@ -14,6 +14,8 @@ jobs:
       - uses: actions/checkout@v2
 
       - uses: subosito/flutter-action@v1.4.0
+        with:
+          channel: 'dev'
 
       - name: Doctor
         run: flutter doctor

CHANGELOG.md

@@ -1,3 +1,8 @@
+## 0.1.0-nullsafety.0 - Jan 15, 2021
+
+-   Migrate this package to null safety.
+-   Sdk constraints: `>=2.12.0-0 <3.0.0` based on beta release guidelines.
+
 ## 0.0.2 - Jan 15, 2021
 
 -   Internal refactor

lib/src/common.dart

@@ -8,10 +8,10 @@ Stream<R> toStreamWithTransform<T extends Listenable, R>(
   T listenable,
   R Function(T) transform,
 ) {
-  StreamController<R> controller;
-  VoidCallback listener;
+  final controller = StreamController<R>();
+  VoidCallback? listener;
 
-  final onListenOrOnResume = () {
+  controller.onListen = () {
     assert(listener == null);
     try {
       listenable
@@ -21,26 +21,13 @@ Stream<R> toStreamWithTransform<T extends Listenable, R>(
     }
   };
 
-  final createOnPauseOrOnCancel = ([bool closeOnError = false]) {
-    return () {
-      assert(listener != null);
-      try {
-        listenable.removeListener(listener);
-        listener = null;
-      } catch (_ /*Ignore*/) {
-        if (identical(closeOnError, true)) {
-          controller.close();
-        }
-      }
-    };
+  controller.onCancel = () {
+    assert(listener != null);
+    try {
+      listenable.removeListener(listener!);
+      listener = null;
+    } catch (_ /*Ignore*/) {}
   };
 
-  controller = StreamController<R>(
-    onListen: onListenOrOnResume,
-    onPause: createOnPauseOrOnCancel(true),
-    onResume: onListenOrOnResume,
-    onCancel: createOnPauseOrOnCancel(),
-  );
-
   return controller.stream;
 }

lib/src/streamx.dart

@@ -7,7 +7,7 @@ extension StartWithExtension<T> on Stream<T> {
   /// Prepends a value to the source [Stream].
   Stream<T> startWith(T Function() seededProvider) {
     final controller = StreamController<T>(sync: true);
-    StreamSubscription<T> subscription;
+    late StreamSubscription<T> subscription;
 
     controller.onListen = () {
       controller.add(seededProvider());

lib/src/value_listenable_to_value_stream.dart

@@ -1,7 +1,7 @@
 import 'dart:async' show Stream, StreamSubscription;
 
 import 'package:flutter/foundation.dart' show ValueListenable;
-import 'package:rxdart/rxdart.dart' show ErrorAndStackTrace, ValueStream;
+import 'package:rxdart/rxdart.dart' show ValueStream, ValueWrapper;
 
 import 'common.dart';
 import 'streamx.dart';
@@ -22,40 +22,25 @@ extension ValueListenableToValueStream<T> on ValueListenable<T> {
   ///
   /// If [replayValue] is true, the returned [ValueStream] will replay latest value when listening to it.
   /// Otherwise, it does not.
-  ValueStream<T> toValueStream({bool replayValue = false}) =>
+  ValueListenableStream<T> toValueStream({bool replayValue = false}) =>
       ValueListenableStream<T>(this, replayValue);
 }
 
 /// A Single-Subscription Stream will emits data when [ValueListenable.value] changed.
 class ValueListenableStream<T> extends Stream<T> implements ValueStream<T> {
   final ValueListenable<T> _valueListenable;
   final bool _replayValue;
-  Stream<T> _stream;
+  Stream<T>? _stream;
 
   /// Construct a [ValueListenableStream] from [ValueListenable].
   ValueListenableStream(this._valueListenable, this._replayValue);
 
-  @override
-  bool get isBroadcast => false;
-
-  @override
-  ErrorAndStackTrace get errorAndStackTrace => null;
-
-  @override
-  bool get hasError => false;
-
-  @override
-  bool get hasValue => true;
-
-  @override
-  T get value => _valueListenable.value;
-
   @override
   StreamSubscription<T> listen(
-    void Function(T) onData, {
-    Function onError,
-    void Function() onDone,
-    bool cancelOnError,
+    void Function(T)? onData, {
+    Function? onError,
+    void Function()? onDone,
+    bool? cancelOnError,
   }) {
     if (_replayValue) {
       _stream ??=
@@ -64,11 +49,21 @@ class ValueListenableStream<T> extends Stream<T> implements ValueStream<T> {
       _stream ??= _valueListenable.toStream();
     }
 
-    return _stream.listen(
+    return _stream!.listen(
       onData,
       onError: onError,
       onDone: onDone,
       cancelOnError: cancelOnError,
     );
   }
+
+  @override
+  bool get isBroadcast => false;
+
+  @override
+  Never get errorAndStackTrace =>
+      throw StateError('This Stream always has no error!');
+
+  @override
+  ValueWrapper<T> get valueWrapper => ValueWrapper(_valueListenable.value);
 }

pubspec.lock

@@ -94,7 +94,7 @@ packages:
       name: rxdart
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "0.25.0"
+    version: "0.26.0-nullsafety.1"
   sky_engine:
     dependency: transitive
     description: flutter

pubspec.yaml

@@ -1,17 +1,17 @@
 name: listenable_stream
 description: Convert Listenable (eg. ChangeNotifier), ValueListenable(eg. ValueNotifier) to Stream / ValueStream.
-version: 0.0.2
+version: 0.1.0-nullsafety.0
 author: Petrus Nguyễn Thái Học <hoc081098@gmail.com>
 homepage: https://github.com/Flutter-Dart-Open-Source/listenable_stream.git
 repository: https://github.com/Flutter-Dart-Open-Source/listenable_stream.git
 issue_tracker: https://github.com/Flutter-Dart-Open-Source/listenable_stream/issues
 
 environment:
-  sdk: ">=2.7.0 <3.0.0"
+  sdk: ">=2.12.0-0 <3.0.0"
   flutter: ">=1.17.0"
 
 dependencies:
-  rxdart: ^0.25.0
+  rxdart: ^0.26.0-nullsafety.1
   flutter:
     sdk: flutter